Michigan's Legislature is expected to pass legislation Tuesday that would bar contracts requiring employees to pay union dues as a condition of employment. The proposed right-to-work law has infuriated union leaders in a state considered the heart of the union movement.

Republican leaders pushing the bill closely watched the fights over labor rights going on across the Midwest, but it wasn't Ohio or Wisconsin that prompted them into action. Many leaders in the public and private sector looked to their neighbor to the immediate south.

"Our members tell us routinely that they are aggressively recruited to other states, most notably freedom-to-work states like Indiana," says Jim Holcomb of the Michigan Chamber of Commerce.

Holcomb says his members have been worried about watching jobs go across the border to Indiana since that state became a right-to-work one.

"Absolutely there's an immediate nature to this, and the positive impact as soon as this bill goes into effect is now we're at least starting on equal footing with those other states and we can sell all the benefits of Michigan," says Holcomb.

Legislators and business leaders in smaller industries and in the western part of the state away from the auto industry have pushed the hardest for right-to-work. Chrysler, Ford and General Motors have stayed out of the fight.

"I don't think that they see, well, if this is right-to-work then we are going to start investing more here. It's not that big of an issue for the Detroit Three that are already unionized," says Kristin Dziczek of the Center for Automotive Research.

The legislation covers both private and public sector workers. On Tuesday, thousands of union members are converging on Lansing, the capital.

Labor leaders had been watching the battles in Wisconsin and Ohio, and that's why during the November election they put a measure on the ballot that would have enshrined collective bargaining rights into the state's constitution.

"Organized labor took that risk, in putting the issue on the ballot, that they would win. They did not win. They got clobbered," says Bill Ballenger, who publishes the newsletter Inside Michigan Politics."Some would argue that they kind of brought this on themselves because they emboldened the people in the Legislature who were most eager to pass right-to-work. The Republicans felt, 'OK, this is it. The window is closing. Now is the time. If we don't do it now, we're probably never going to get this done.' "

Republicans in the statehouse will lose members in January, and they wouldn't have had the guaranteed votes to pass the legislation then.

Ballenger says Republicans in Michigan have learned another key lesson from their fellow Midwesterners: changing the recall statute language in the state to make it tougher to recall legislators.

Leaders of organized labor are vowing to fight not just today, but in the future as well. They acknowledge that they may have to wait until 2014 for any resolution. That's when the entire Legislature and the governor are up for re-election.